A London-based environment group claimed that North Koreans dispatched to work on Chinese fishing boats to earn foreign currency for the regime are being exploited.

The New York Times on Sunday quoted a report by the London-based Environmental Justice Foundation, which interviewed 19 Indonesian and Filipino shipmates who said they had worked with North Koreans.

According to their testimony, although the Chinese tuna longliners operating in the Indian Ocean docked in Somalia, Mauritius, Australia and Madagascar, the North Koreans were always transferred without disembarking.

The Chinese captains are assumed to have restricted their disembarkment to prevent them from being seen by the port authorities, as their overseas labor is in violation of United Nations Security Council(UNSC) resolutions.

While Indonesian sailors earned around 330 U.S. dollars a month, the North Koreans' salaries were reportedly sent directly to their government to be spent toward its nuclear weapons program.

Chinese Foreign Ministry spokesperson Lin Jian said on Monday that he did not know the specifics of such claims, but that related cooperation with the North is conducted within the boundary of international law.